• Journal of Legislation Research
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• no.44
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• pp.155-184
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• 2013

This study takes a critical perspective that current vertical regulatory framework for broadcasting, telecommunications, films and games cannot cope with media development in the age of convergence. Changes in media environment mitigate the uniqueness of terrestrial television causing doubts as to why television contents should be treated more strictly than the rest of media contents. Consensus is being reached that horizontal regulation would be the appropriate regulatory measure for media contents. However, which content should be aligned to what level of regulations have not been fully dealt with. The paper shows that the current regulatory framework which is established according to each delivery platform is no longer valid in convergent media environment. It shows why all content regulation should be applied in platform neutral manner. Then it also suggests both short and long term regulatory changes that need to be made in order to meet the future challenges in media convergence era.

• Proceedings of the KIEE Conference
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• 2006.04b
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• pp.226-228
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• 2006

This paper presents the two lossless auxiliary inducors-assisted voltage source type half bridge(single ended push pull:SEPP) series resonant high frequency inverter for induction heated fixing roller in copy and printing machines. The simple high-frequency inverter treated here can completely achieve stable zero current soft switching (ZCS) commutation forwide its output power regulation ranges and load variations under constant high frequency pulse density modulation (PDM) scheme. Its transient and steady state operatprinciple is originally described and discussed for a constant high-frequency PDM control strategy under a stable ZCS operation commutation, together with its output effective power regulation charactertics-based on the high frequency PDM strategy. The experimenoperating performances of this voltage source SEPP ZCS-PDM series resonant high frequency inverter using IGBTs are illustrated as compared with computer simulation results and experimenones. Its power losses analysis and actual efficiency are evaluated and discussed on the basis of simulation and experimental results. The feasible effectiveness of this high frequency inverter appliimplemented here is proved from the practical point of view.

• Journal of Electrical Engineering and Technology
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• v.12 no.6
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• pp.2208-2218
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• 2017

To resolve overload in a distribution system, a distribution system operator (DSO) often performs a load transfer using normally open tie points and switches in the distribution line. During this process, the distribution system is momentarily operated in closed-loop operation. A closed-loop current in the distribution system can cause a power failure due to excess breaking current in the circuit breakers and reclosers. Therefore, it is necessary to calculate the closed-loop current exactly. However, if there are a large number of distributed generation (DG) systems in the distribution system, such as energy storage systems (ESS), they might obstruct the closed-loop operation based on bidirectional power flow. For quick and precise operation of a closed-loop system, the ESS has to regulate the power generation while satisfying closed-loop operation in the worst cases. We propose a strategy for balanced power regulation of an ESS. Simulations were carried out using PSCAD/EMTDC, and the results were compared with calculation results.

• Journal of Power Electronics
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• v.18 no.4
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• pp.975-984
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• 2018

This work presents a high efficiency phase shifted full bridge (PSFB) DC-DC converter for use in the second stage of a battery charger for neighborhood electrical vehicle (EV) applications. In the design of the converter, Lithium-ion battery cells are preferred due to their high voltage and current rates, which provide a high power density. This requires wide range output voltage regulation for PSFB converter operation. In addition, the battery charger works with a light load when the battery charge voltage reaches its maximum value. The soft switching of the PSFB converter depends on the dead time optimization and load condition. As a result, the converter has to work with soft switching at a wide range output voltage and under light conditions to reach high efficiency. The operation principles of the PSFB converter for the continuous current mode (CCM) and the discontinuous current mode (DCM) are defined. The performance of the PSFB converter is analyzed in detail based on wide range output voltage and load conditions in terms of high efficiency. In order to validate performance analysis, a prototype is built with 42-54 V / 15 A output values at a 200 kHz switching frequency. The measured maximum efficiency values are obtained as 94.4% and 76.6% at full and at 2% load conditions, respectively.

• Journal of Power Electronics
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• v.18 no.1
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• pp.23-33
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• 2018

Silicon Carbide (SiC) MOSFET belongs to the family of wide-band gap devices with inherit property of low switching and conduction losses. The stable operation of SiC MOSFET at higher operating temperatures has invoked the interest of researchers in terms of its application to high power density (HPD) power converters. This paper presents a performance study of SiC MOSFET based two-phase interleaved boost converter (IBC) for regulation of avionics bus voltage in more electric aircraft (MEA). A 450W HPD, IBC has been developed for study, which delivers 28V output voltage when supplied by 24V battery. A gate driver design for SiC MOSFET is presented which ensures the operation of converter at 250kHz switching frequency, reduces the miller current and gate signal ringing. The peak current mode control (PCMC) has been employed for load voltage regulation. The efficiency of SiC MOSFET based IBC converter is compared against Si counterpart. Experimentally obtained efficiency results are presented to show that SiC MOSFET is the device of choice under a heavy load and high switching frequency operation.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.199-210
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• 2019

Virtual Advertising, which was introduced exclusively in sports casting programs in 2010, has enlarged its scope to terrestrial TV networks' sports news, entertainment shows, and dramas by 2015. Such advertising deregulation allows broadcasting business operators to insert more various virtual advertising methods into TV programs. Despite recent evaluation that virtual advertising was deregulated to a large degree, it is still inadequate compared to foreign state of affairs and has a lot of room for growth. Therefore, this research explores a literature review of virtual advertising in other countries and considers possible ways for virtual advertising in Korea to move forward. Additionally, through in-depth interview with seven virtual advertising experts, the research unravels positive and negative impacts of virtual advertising as well as its current state of affairs and struggles. This research also analyses the regulation of virtual advertising and finally explores possible revitalization strategies. The results of the research show that it is necessary to first improve the viewers' favorable concerning virtual advertising in order to revitalize virtual advertising. Revitalization will also require a clarification of regulation as well as a more unified and consistent content review and rating system. Furthermore, it is imperative that data of advertising impact will be accessible to advertisers and that advertising regulation will loosen. Revitalization will also require a clarification of regulation as well as a more unified and consistent content review and rating system. Furthermore, it is imperative that data of advertising impact will be accessible to advertisers and that advertising regulation will loosen. It is necessary to further develop new techniques and creators of virtual advertising. The research suggests strategies and alternative paths for the growth and revitalization of the virtual advertising market in light of recently revised law.

• Development and Reproduction
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• v.4 no.2
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• pp.243-250
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• 2000

To find the mechanism underlying the ADP-induced increase in the outward current in ovulated mouse oocytes, we examined changes in voltage-dependent currents using the whole cell voltage clamp technique and the internal perfusion technique. Eggs were collected from the oviduct of superovulated mice with PMSG and hCG. Membrane potential was held at -60 mV (or -80 mV in the case of recording $Ca^{2＋}$ currents) and step depolarizations or hyperpolarizations were applied for 300 ms. By step depolarizations, outward currents comprising steady-state and time-dependent components were elicited. They were generated in response to the positive potential more than 20 mV with severe outward rectification and were blocked by external TEA, a specific $K^{＋}$ channel blocker, suggesting that they be carried via $K^{＋}$ channels. Internally-perused 5 mM ADP gradually increased outward $K^{＋}$ currents (IK) 1 min after perfusion of ADP and reached slowly to maximum (150~170％) 5 min later over the positive potential range, implying that ADP might not be acted directly to the $K^{＋}$ channels. IK were decreased by 5 mM ATP without affecting the steady-state component of outward current. In contrast to the effect of ADP and ATP on IK, both effect of ATP and ADP on inward $Ca^{2＋}$ currents (ICa) could not be detected due to the continuous decrease in current amplitudes with time-lapse ("run-down" phenomena). To check if there is a G protein-involved regulation in the ionic current of mouse oocytes, 1 mM GTP was applied to the cytoplasmic side, and the outward current and inward currents were recorded. ICa was promptly increased in the presence of GTP whereas IK was not changed. from these results, it is concluded that the ATP-dependent regulation is likely linked in the ADP-induced increase in the outward $K^{＋}$ current, and G protein-involved cellular signalling might affect ion channels carrying $Ca^{2＋}$ and $K^{＋}$ in mouse oocytes.

• Korean Journal of Childcare and Education
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• v.10 no.2
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• pp.93-110
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• 2014

The purpose of this study was to examine the use of emotional regulation strategies of 3-year-old infants in frustrating situations and the correlation between infants' emotional strategies and their mothers' responsive strategies. In the current study, 33 dyads of infant-mother were observed in the laboratory. Stansbury and Sigman's (2000) experimental instrument was revised and complemented according to Korean culture, and it was categorized into 5 measures for infants' use of emotional regulation strategies in frustrating situations and their mothers' responsive strategies: comforting, instrumental, cognitive reappraisal, distraction, and others. As a result, infants' emotional regulation strategies and their mothers' responsive strategies were categorized as 5 such strategies. The findings of this study showed that 3-year-old infants used complex strategies including cognitive reappraisal. They used instrumental strategy most during a 'clean up' frustrating situation and distraction strategy during a 'candy given then denied' situation. There was significant correlation between infants' emotional regulation strategies and their mothers' responsive strategies.

• The Journal of the Korea Contents Association
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• v.18 no.12
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• pp.185-196
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• 2018

Current study was conducted to examine the mediating effect of maladaptive cognitive emotion regulation strategies and negative affect on the relationship between perceived stress and smartphone addiction of adults and to explore suggestions for counseling adults with smartphone addiction symptoms. Three hundred adults(146 males, 154 females) were administered perceived stress scale, maladaptive cognitive emotion regulation strategy scale, negative affect scale, and smartphone addiction scale. The main results are summarized as follows: First, perceived stress had positive influence on smartphone addiction. Second, negative affect showed mediating effect on the relationship between perceived stress and smartphone addiction. Third, maladaptive cognitive emotion regulation strategies did not show mediating effect on the relationship between perceived stress and smartphone addiction. Forth, maladaptive cognitive emotion regulation strategies and negative affect showed double mediating effect on the relationship between perceived stress and smartphone addiction. Based on the above results, it was suggested to include stress management and relief of negative affect through modification of maladaptive cognitive emotion regulation strategies in the treatment program for adults at high risk of smartphone addiction.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.151-152
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• 2011

This paper describes a cross-regulation characteristics of a multi-output LLC resonant converter widely used in consumer electronics. The output characteristics of the multi-output LLC converter is derived from the assumption that the current and voltage to flow through the resonant network is sinusoidal and the duty loss is investigated. The simulation results are provided to verify the theoretic results.